Caribbean - Central America Weather

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
446 AM AST Mon Apr 7 2025

.SYNOPSIS...

Variable, seasonal weather to gradually shift towards a wetter
pattern, with lighter winds and warmer-than-normal temperatures.
Marine and coastal conditions continue improving, however, small
craft and beachgoers should exercise caution. A northeasterly
long- period swell will arrive later tomorrow night, bringing
hazardous marine and coastal conditions throughout the workweek.

&&

.SHORT TERM...Today through Wednesday...

Clear to partly cloudy skies prevailed across Puerto Rico and the
U.S. Virgin Islands during the overnight hours. Passing trade wind
showers were noted across most coastal areas of eastern and northern
Puerto Rico. The Doppler radar estimated up to half an inch of rain
from Luquillo to Canovanas, and a few hundredths over St. Croix.
Minimum temperatures were from the low to mid-70s across the lower
elevations to the upper 50s and low 60s across the higher mountain
valleys. The wind was from the east up to 10 mph with gusts between
14 and 20 mph across coastal areas.

A surface high pressure north of the area will move and strengthen
over the central Atlantic during the short-term period. In response,
moderate to locally fresh east to southeast winds are expected to
prevail during the next few days. Fragmented low-level cloudiness
and showers from an old frontal boundary just east of the Leeward
Islands, are expected to move across the islands later today. This
shallow layer of moisture is then expected to linger over the region
through at least Tuesday. The precipitable water content is forecast
to gradually increase to around 1.50 inches between Tuesday and
Wednesday.

At the upper levels, a broad trough over the northeastern Caribbean
will continue to amplify, promoting instability aloft and increasing
the potential for isolated thunderstorm development due to colder-
than-normal 500 mb temperatures of -8C and -9C through at least
Tuesday. Therefore, isolated thunderstorms are expected to develop
over western Puerto Rico each day. By late Wednesday, an induced low-
level trough is expected to develop over the east/southeastern
Caribbean, and moisture will continue to pool near the local area.
However, an upper level ridge will move over the islands, and
warming of the 500 mb temps to near -5C is expected. This should
suppress thunderstorm development in the afternoon over NW PR,
however, showers are still expected to develop. Across the USVI,
passing showers will gradually increase from today through at least
Tuesday afternoon. However, flooding is not anticipated.

&&

.LONG TERM...Thursday through Monday...

The wetter pattern may start earlier than expected. Latest model
guidance shows an increase of moisture content in the low to mid
levels by late Thursday into Friday. This is due the high surface
pressure in the Western Atlantic dragging the remnants of another
frontal boundary and an induced low-level trough southeast of the
Caribbean. PWAT values will continue increasing to above
climatological normals (1.7 - 1.8 inches). The mid-level ridge is
expected to move over the CWA and linger for the next few days,
once again warming 500 mb temperatures (around -4 Celsius) and
inhibiting deep convection activity. However, enough low to mid
level moisture will promote frequent moderate to locally strong
showers each day, moving along windward sections in the nights and
early mornings, then enhance over interior and western/northwestern
PR in the afternoons. Expected rainfall accumulations will result
in mostly ponding of water in roadways and poorly drained areas,
promoting urban and small stream flooding. As the high surface
pressure migrates eastward and a polar trough deepens, a col
area will move close to the region by late Monday, slowing winds
and favoring the development of showers across the region.

With the east-southeasterly flow dominating the period, warmer and
moist air will filter into the region, increasing temperatures to
above normal for this time of the year. However, extreme heat danger
will remain low.

&&

.AVIATION...

(06Z TAFs)

Mainly VFR conditions are expected to prevail across all terminals
during the next 24 hours. However, TSRA expected to develop in and
around TJBQ btw 07/16-22z, which may cause tempo MVFR to brief IFR
conds. East winds will increase between 14-18 kt with sea
breeze variations and stronger gusts after 07/13z.

&&

.MARINE...

A broad surface high pressure over the western Atlantic will
continue promoting moderate to locally fresh easterly winds for the
next few days. As a result, small craft should continue to exercise
caution. A northeasterly long period swell will arrive later tomorrow
night, increasing seas and deteriorating marine conditions
throughout the rest of the workweek.

&&

.BEACH FORECAST...

The moderate risk of rip currents continues for northern/eastern
PR, Culebra, and the U.S. Virgin Islands today. A northeasterly
long period swell is expected to arrive late tomorrow, Tuesday,
increasing seas and deteriorating marine and coastal conditions
throughout the rest of the workweek. The risk of rip currents is
very likely to increase later by Tuesday night into Wednesday.
Beachgoers should exercise caution and stay updated regarding
beach conditions.

&&

.FIRE WEATHER...

Winds will turn from the southeast later today, increasing up to
20 mph and gusts up to 27 mph over the southern coastal plains.
Latest station reports in Guanica show KDBI values increasing
(640), as well as Maricao and Cabo Rojo (397 and 370 respectively).
For Guanica, these values continue meeting fire weather criteria.
Additionally, southern coastal plains of PR continue with a
precipitation deficit and very dry soils, and relative humidities
are expected to once again drop below thresholds (around 41%).
The combination of these factors contribute to the rapid fire
spread. Therefore, the fire danger risk will once again be
elevated today for the southern coastal plains of Puerto Rico. A
Fire Danger Statement (RFDSJU) will be issued for portions of
southern Puerto Rico.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
448 AM AST Tue Apr 8 2025

.SYNOPSIS...

Variable, seasonal weather will gradually shift to a wetter
pattern for the second part of the workweek onwards, with lighter
winds and warmer- than- normal temperatures. A northeasterly
long- period swell will arrive later today, deteriorating marine
and coastal conditions and resulting in Small Craft Advisories and
a High Risk of Rip Currents.

&&

.SHORT TERM...Today through Thursday...

Variably cloudy skies prevailed across Puerto Rico and the U.S.
Virgin Islands during the overnight hours. The remnants of an old
front brought low-level cloudiness and showers across the U.S.
Virgin Islands before midnight first and then over eastern Puerto
Rico and between the coastal waters of the islands. Rainfall amounts
were near a quarter of an inch in St. John to near half an inch
across the eastern coastal areas of PR. Minimum temperatures were
from the low to mid-70s across the lower elevations of the islands
to the low and mid-60s across the higher elevations of PR. The wind
was from the east at 8 to 12 mph with gusts up to 22 mph across
coastal areas.

High surface pressure to the north will gradually strengthen over
the central Atlantic over the short-term period. As a result,
moderate to locally fresh east-southeast winds are expected to
persist over the next few days. Additionally, patches of low-level
moisture and showers from an old frontal boundary approaching from
the east are forecast to linger across the region through Wednesday.
By late Wednesday, an induced low-level trough is anticipated to
develop over the east/southeastern Caribbean, bringing continued
moisture pooling near the local area, while another band of moisture
associated with another old frontal boundary moves just northeast of
the northern Leeward Islands by Thursday. However, an upper-level
ridge will build over the islands, and 500 mb temperatures are
expected to warm to around -5C. Though afternoon showers are still
likely in the usual areas, this will likely suppress significant
thunderstorm development.

&&

.LONG TERM...Friday through Tuesday...

The long-term forecast continues on track, transitioning to a wetter
pattern for the weekend and early next week. ESE-SE winds will
dominate the forecast period due to the high surface pressure that
will continue migrating eastward. Under that pattern, a
combination of the remnants of a frontal boundary and an induced
low- level trough close to the Leeward Islands will move across
the CWA during the weekend. Model guidance continues highlighting
above normal PWAT values for Saturday and Sunday (around 1.9
inches). High moisture content pooling into the region will
increase shower activity, mainly in windward sections during the
night into the morning hours. The combination of local effects,
diurnal heating, and sea breeze convergence will enhance
convection activity in the afternoons, mainly over interior and
western/northwestern Puerto Rico. However, a mid- level ridge
will move south of the region and linger through the forecast
period, warming 500 mb temperatures (-4 to -5 Celsius) and promote
stability aloft. As the surface high pressure moves eastward and
a polar trough deepens, a col area will move north of the region,
slowing winds. Showers in the afternoon will mostly likely stay
longer than expected. The latest model solutions highlight another
frontal boundary approaching the region by Tuesday, increasing
moisture content to above normal. The main hazard during the
forecast period will mostly be flooding, as rainfall
accumulations in the afternoons will increase promote ponding of
water in roadways and poorly drained areas, along with urban and
small streams flooding.

Confidence in model guidance keeps increasing regarding
temperatures expected to be above normal this weekend. With the
southeasterly flow and enough moisture content, limited risk of
heat along urban and coastal areas of Puerto Rico.

&&

.AVIATION...

(06Z TAFs)

Mainly VFR conditions are expected to prevail across all terminals.
However, SHRA expected to increase across the islands today due to
the arrival of the remnants of an old frontal boundary. This may
cause SCT/BKN cigs btw FL030-FL080, and brief periods of +RA across
the area terminals thru 09/00z. Also, TSRA expected to develop in
and around TJBQ btw 08/16-22z, which may cause tempo MVFR to brief
IFR conds. East-southeast winds will increase between 12-16 kt with
sea breeze variations and stronger gusts after 08/13z.

&&

.MARINE...

A broad surface high pressure over the western Atlantic will
continue to promote moderate to locally fresh easterly winds for the
next few days. A northeasterly long period swell will arrive later
today, increasing seas and deteriorating marine conditions throughout
the rest of the workweek. A Small Craft Advisory will be in effect
for the Atlantic coastal and offshore waters and the Anegada Passage
from this evening through Wednesday evening.

&&

.BEACH FORECAST...

Latest buoy observations are reporting wave heights between 7 - 9
feet and swell periods around 14 - 16 seconds. This swell will
gradually increase the breaking waves from noon today onwards.
Therefore, a high risk of rip currents is now in effect for the
northern beaches of Puerto Rico, from Aguadilla to Fajardo,
Culebra, and the U.S. Virgin Islands through late tomorrow night.
Heed the advice of lifeguards, beach patrol flags and signs.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
505 AM AST Tue Jun 13 2023

.SYNOPSIS...

Partly cloudy skies prevailed across the local islands overnight
with passing showers noted across eastern Puerto Rico, the US Virgin
Islands and local waters. Rainfall totals associated with these
showers were minimal.

An increased chance of showers and thunderstorms is expected
through at least Wednesday. Thursday onwards, fair weather
conditions are expected to prevail each day. Heat indices are
expected from 102 to 111 degrees today, as a result, there is a
Heat Advisory in effect from 10 am this morning to 5 pm this
afternoon.

&&

.SHORT TERM...Today through Thursday...

The upper level trough is found over Florida and will advance to
eastern Cuba by Thursday evening, however the upper level high at
250 mb will remain generally just east of the Leeward Islands with
some ridging over the local area. This will keep mid levels from 13-
39 Kft relatively dry through the early part of the day with only
modest moisture (50-70% RH) at those levels from around midday
Tuesday to early Thursday morning (15/06Z). Drier mid-levels return
and continue into the long term period. While 500 mb temperatures
are relatively warm and hovering around minus 5 degrees, surface
temperatures are still running above normal and will create somewhat
unstable conditions. A few thunderstorms were seen in western Puerto
Rico Monday afternoon, and a number of thunderstorms were seen over
the eastern tip of the Dominican Republic overnight. As the heat and
humidity persist over the area, widely scattered thunderstorms are
expected to develop each afternoon--mainly over western Puerto Rico.
Tonight and Wednesday night may also see a few thunderstorms over
the local waters.

Surface high pressure continues, with little movement, over the
central Atlantic but east of 60 degrees west. This will bring a
return of southeasterly surface winds to the forecast area and which
will become more noticeable tonight through Thursday. Although
moisture has increased, these southeasterly winds will keep
temperatures on the north coast and the Culebrinas River Valley
abnormally warm with temperatures generally holding in the lower 90s
with a few exceptions today owing to clouds and rain. Because of
this, a heat advisory was issued for today from the northern and
western coasts of Puerto Rico including Culebra, and the eastern
slopes. Heat indices are expected from 102 to 111 degrees in these
areas.

&&

.LONG TERM...Friday through Wednesday...

The mid to upper level ridge, which has been in place across the
eastern Caribbean into the tropical Atlantic, is expected to erode
the upcoming weekend into the next work week. At lower levels,
surface high pressure across the central Atlantic will continue to
yield east southeast winds much of the forecast period with the
local pressure gradient tightening somewhat by the end of the cycle.
Although the latest guidance suggested an increased chance of
afternoon convection under the weakening ridge, precipitable water
values will remain below seasonal thresholds. At this time, best
moisture advection is expected by midweek next week.

Therefore, continue to expect mainly fair weather conditions
each day with limited afternoon convection focused across western
areas of Puerto Rico. Hazy Friday and Saturday. Major hazard
continue to be heat indices above 100 degrees under the
aforementioned east southeast wind flow.

&&

.AVIATION...

Isold -SHRA ovr ern half of PR til arnd 13/17Z then bcmg sct-numrs
SHRA--mainly ovr wrn and interior PR with isold TSRA. Sfc winds arnd
10 kt bcmg 10-18 kt with gusts to 26 kts psbl nr SHRA and vcty
coastline. Max winds 15-20 kt blo FL250.

&&

.MARINE...

East southeast winds between 15 and 20 knots will induce choppy seas
across most of the regional waters. Therefore, small craft operators
should exercise caution. In general, seas should remain 6 feet or
less across the local waters. There is a moderate risk of rip
currents across the north coast of Puerto Rico.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
435 AM AST Thu Apr 10 2025

.SYNOPSIS...

A frontal boundary approaching Puerto Rico and the U.S. Virgin
Islands from the west will enhance moisture pooling over the
islands from today onwards. Showery conditions are expected, with
the heaviest activity over the western portions of Puerto Rico
during the afternoon hours. A fading long period northeasterly swell
will continue to promote life-threatening rip currents along the
north and east-facing beaches in PR and the US Virgin Islands
through this afternoon.

&&

.SHORT TERM...Today through Saturday...

We observed a calm night with cloudy skies. The Doppler Radar
detected some showers moving across the US Virgin Islands and the
eastern sections of PR, while the rest of the islands did not
observe rain at all. Winds were mainly from the east-southeast but
influenced by land breeze variations, and the local network reported
winds mainly between 5 and 10 mph. Minimum temperatures reached the
low 60s or even the mid to upper 50s along mountains and valleys,
while the thermometer across coastal locations reached the low 70s.

A frontal boundary approaching the region of PR and the USVI from
the west will enhance moisture pooling over the islands from today
(Thursday) into the weekend. Although a ridge is building aloft, low-
level convergence and an induced pre-frontal trough will increase
the chance of transitioning into a moist, showery weather pattern.
Even though we anticipate periods without rain, the intensity and
coverage of shower activity will increase by mid-morning today into
the evening, affecting first the windward locations, followed by
strong afternoon convection across the mountains and northwest
quadrant of PR. There is an elevated chance of flooding rains
producing urban and small stream flooding, especially in the
afternoon or early evening. Additionally, under a southeast wind
flow, the "San Juan Streamer" will develop downwind from El Yunque,
impacting portions of the San Juan Metropolitan area.

A fading long-period northeasterly swell will continue to promote
the formation of life-threatening rip currents along the north and
east-facing beaches in PR and the US Virgin Islands. Therefore, a
High Risk of Rip currents is in effect for the north-facing beaches
of PR, Culebra, and the US Virgin Islands. Please exercise caution
when choosing to visit beaches or other water-related activities.

There is a moderate to moderate/high chance of observing the wet and
showery weather on Friday and Saturday. Model guidance suggests the
frontal boundary remaining out of the regions but at a favorable
position to induce low-level pre-frontal troughs over the islands,
pooling abundant moisture over the Northeast Caribbean. Under this
pattern, and if all the necessary ingredients align, we can expect
an evolving wet and unstable pattern on Friday and Saturday, with
the formation of flooding rains and thunderstorm activity,
especially in the afternoon and evening hours.

.LONG TERM...Sunday through Wednesday...

Wet and unstable weather conditions will predominate during the long
term period with the presence of a lingering frontal system north of
the area with characteristics of an atmospheric river over the
Atlantic region. The latest precipitable water content (PWAT)
guidance continues to suggest above-normal climatological values of
1.8 to 2.2 inches through the end of the period. Under this high
moisture pattern, showers are expected throughout the day across the
islands with the heaviest activity over the western and southwestern
portions of Puerto Rico. By the beginning of next week a strong
building high pressure located over the western Atlantic will begin
to move toward the central Atlantic, promoting northeasterly winds
through mid-week. Then, winds will shift from the southeast as the
surface high migrates eastwards over the Atlantic Ocean. With the
expected weather scenario and the development of shower activity
each day, the potential for urban and small stream flooding
increases due to soil saturation. At this time, an increase in
temperatures is anticipated as well for next week. The 925mb
temperatures will increase to above-normal climatological values
everyday. Highs will be at the mid to upper 80s across the coastal
and urban areas, and from the upper 70s to low 80s in the
mountains and higher elevations.

&&

.AVIATION...
(06z TAFs)

VFR conditions will persist throughout the forecast period.
Occasional SHRA/-SHRA may impact IST/ISX/JSJ at times. +SHRA and
isolated TSRA will create MVFR conditions or even IFR between
10/16-23z and a low risk, possibly at JBQ and near JSJ if the San
Juan streamer develops. This convection will also create mountain
obscurations. Winds will be mainly calm to light and variable
through 10/13z, returning from the E-ESE at 10-15 kt, with higher
gusts and sea breeze variations, but gusty near TSRA/SHRA.

&&

.MARINE...

A broad surface high pressure over the western Atlantic will continue
to promote moderate to locally fresh easterly winds for the next few
days. A fading long period northeasterly swell will promote seas up
to 6 feet across the regional waters today. Therefore, small craft
operators should continue to exercise caution across the regional
waters. Seas will continue to improve over the next few days.

&&

.BEACH FORECAST...

A fading long period northeasterly swell will continue to promote
the formation of life-threatening rip currents along the north
and east-facing beaches in PR and the US Virgin Islands. Therefore,
a High Rip Current Risk remains in effect through this afternoon
across the northern exposed beaches of Puerto Rico, Culebra and
St. Croix. Please, heed the advice of lifeguards, beach patrol
flags and signs.

&&

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
349 AM AST Fri Apr 11 2025

.SYNOPSIS...

A frontal boundary located over Hispaniola will continue to
approach Puerto Rico and the U.S. Virgin Islands from the west
enhancing the moisture content across the islands over the
weekend. Showery conditions are expected, with the heaviest
activity with isolated thunderstorms possible over the
northwestern quadrant of Puerto Rico each day. Above normal
temperatures are anticipated for the next few days with heat
indices above 102 degrees each afternoon.

&&

.SHORT TERM...Today through Sunday...

Once the showers dissipated over western Puerto Rico, mostly
tranquil conditions prevailed over land, while a persisting
thunderstorms lingered about 35-40 miles north of Isabela.
Temperatures cool down to the mid and upper 70s in the coastal
areas, and near 70 in the mountain.

Taking a look at the infrared satellite imagery, the most prominent
feature is a cold front now located over Hispaniola. The interaction
with the front and a high pressure over the eastern Atlantic will
keep a moderate southeasterly wind flow, with plenty of moisture
coming from the Caribbean Sea (precipitable water values are
expected to be above 2.0 inches, which is higher than normal). As a
result, another active afternoon is anticipated, mostly for the
interior and northwestern quadrant of Puerto Rico. The rain could be
heavy at times, leading to urban and small stream flooding, rapid
river rises and some mudslides in areas of steep terrain.
Thunderstorms are likely too, with some lightning strikes
anticipated. For eastern Puerto Rico and the Virgin Islands, the
rain will not be as frequent, but showers will still form over the
waters, streaming over these areas, and keeping some roads wet.

For tomorrow, similar conditions are anticipated. Moisture will be
plenty, and the surface wind flow will come out of the southeast,
although lighter, at speeds of 7-8 kts. At around 650 mb (or 11,000
feet) height, the winds will come from the southwest. What this
means is that the rain that forms over the interior could be drifted
across northwest or north-central Puerto Rico. On Sunday, a little
less moisture will be available, but still, afternoon convection
should develop in the afternoon for the interior of Puerto Rico,
with passing showers expected for the east and for the Virgin
Islands. All and all, an elevated flood risk and limited lightning
risk will exist today through Sunday.

With winds coming out of the southeast, temperatures at 925 mb are
nearly two standard deviation above normal. Therefore, heat indices
above 102 degrees are expected each afternoon, for areas that are
not protected by the afternoon cloud deck that develops from the
afternoon showers. Remember to stay hydrated, take breaks in shaded
areas, and don't expose your pets to the heat.

.LONG TERM...Monday through Thursday...

The long term forecast continues on track, with a high moisture
and wet pattern early next week. A building surface high pressure
moving from the western to central Atlantic will promote
northeasterly winds on Monday. Winds will gradually shift from the
east southeast on Tuesday, then becoming from the southeast on
Wednesday as the surface high migrates eastwards. The lingering
frontal boundary located northwest of the area the surface high
pressure will continue to pull moisture from the Caribbean into
the islands. Under this high moisture environment the potential to
observe rainfall activity over the region increases. However, a
mid-level ridge at 500 mb will place over the area promoting
stability aloft and inhibiting the formation of strong convective
activity over the islands during the forecast period. The latest
precipitable water content guidance (PWAT) suggest above-than-
normal climatological values between 1.8 to 2.0 inches. Throughout
the period, showers are likely to form over the western and
northwestern portions of Puerto Rico in the afternoon with periods
of heavy rainfall at times. During the forecast period, the main
hazard will be mostly minor flooding in urban and low-drainage
areas. A warmer trend is expected to continue next week with above
normal temperatures. Highs will be in the upper 80s across the
coastal and urban areas, and from the upper 70s to mid 80s in the
mountains and higher elevations.

&&

.AVIATION...
(06Z TAFS)

Mainly VFR conditions expected to prevail for most of the forecast
period. Passing SHRA will impact TJSJ and the USVI terminals at
times. For TJBQ, from 17-22Z, SHRA and TSRA are expected to develop,
with periods of reduced VIS and low ceilings. Mountain obscuration
is also expected for the western Cordillera Central. Wind are from
the SE at 8-13 kts, with stronger gusts, especially near the SHRA
activity.

&&

.MARINE...

A broad surface high pressure over the western Atlantic will
continue to promote moderate to locally fresh easterly winds for the
next few days. Unstable and wet weather pattern will promote shower
and thunderstorm activity across the regional waters, particularly by
early evening and late night hours for the next few days.

&&

.BEACH FORECAST...

There is a moderate risk of rip currents along the northern,
northwestern and northeastern beaches of Puerto Rico, Culebra,
Vieques and the U.S. Virgin Islands. Life- threatening rip
currents are possible in the surf zone. A low to moderate risk of
rip currents will continue to persist during the weekend.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
358 AM AST Sat Apr 12 2025

.SYNOPSIS...
Showers and thunderstorms will continue to develop each afternoon
across the islands, enhancing the risk for urban and small stream
flooding, as well as mudslides and rapid river rises. The heaviest
activity is expected across north, west and the interior of Puerto
Rico, but showers will also reach the Virgin Islands and eastern
Puerto Rico at times.

&&

.SHORT TERM...Today through Monday...

Calm weather conditions prevailed overnight across the islands. Few
showers moved over the U.S. Virgin Islands and portions of eastern
Puerto Rico, leaving minimal accumulations. However, showers and
thunderstorms were observed over the local Atlantic waters producing
frequent lightning northwest of Aguadilla. Lows were seen in the mid
and upper 70s in the coastal areas of the islands, and in the mid to
upper 60s in the mountains.

A cold front located over the Hispaniola will continue to approach
Puerto Rico and the U.S. Virgin Islands over the weekend. The
interaction of the cold front and a surface high pressure over the
eastern Atlantic will continue to promote light to moderate
southeasterly winds through Sunday. However, another surface high
pressure exiting the eastern U.S. coast will push the cold front
over the local area by late Sunday into Monday morning.

The precipitable water content will remain above-normal
climatological values (2.0 to 2.2 inches) through early next week.
Therefore, active afternoons are anticipated with moderate to heavy
rainfall, particularly over the northwestern quadrant of Puerto
Rico. Thunderstorm are likely as well during the period, producing
frequent lightning over the area. With the expected activity, there
is an elevated potential to observe urban and small stream flooding,
as well as rapid river rises and mudslides.

A warmer trend is expected to continue next week with above-normal
temperatures at the 925mb. Highs will be in the upper 80s to low 90s
across the coastal and urban areas, and in the upper 70s to mid 80s
in the mountains and higher elevations. Heat indices will reach the
102 degrees Fahrenheit this weekend over portions of western and
north-central Puerto Rico. Remember to stay hydrated, wear light
clothes, and take breaks in shaded areas!

.LONG TERM...Tuesday through Saturday...

A surface high pressure will roll eastward from the west, forcing
the frontal boundary to lie down across the region, and thus
providing plenty of moisture through much of the forecast period.
At the surface, a trough will also develop on Tuesday, while
another mid to upper level trough will approach from the west on
Wednesday and Thursday. As these system interact, yet another
surface trough will develop north of the region. All this
instability and moisture will result in active afternoons, with
showers and thunderstorms developing, mostly across the interior,
western and northern Puerto Rico. Something else to consider is
that winds will be mostly from the southeast...on Tuesday, around
10-15 mph, and slowing down after Wednesday, below 10 mph. After
a couple days of rain, soils will be saturated, and rivers will be
running high. Therefore, the risk for urban flooding, rapid river
rises, and mudslides will increase.

By the end of the week, the uncertainly increase, mostly because
the ECMWF model shows a deeper trough reaching the region, but the
GFS does not have such a define feature. The forecast was adjusted
for this period, showing higher probability of precipitation and
amount of rainfall. As is usual, showers will reach eastern
Puerto Rico and the Virgin Islands periodically, but the strongest
activity will impact the interior, western and northern portions
of Puerto Rico.


&&

.AVIATION...
(06Z TAFs)

Mainly VFR conditions are expected to prevail across all terminals
through the period. Passing SHRA will affect the TJSJ, TIST and TISX
at times. However, SHRA/TSRA will affect the TJBQ aft 12/17Z causing
brief MVFR cnds with periods of reduced visibility and low ceilings.
Mntn obsc is expected for along the Cordillera Central today. Winds
will prevail from the SE at 8-15 kts with stronger gusts, mainly
near the strongest SHRA activity.

&&

.MARINE...
A cold front across the western Atlantic will continue to approach
the northeastern Caribbean over the next few days. A broad surface
high pressure will remain anchored over the central Atlantic
promoting light to moderate east to southeast winds through the
weekend. However, another surface high pressure will build over the
western Atlantic and push the front over the local area by early next
week. This will promote moderate to fresh northeast winds from
Monday night onwards. Shower and thunderstorm activity will develop
each day, mainly across the Atlantic waters and the Mona Passage.

&&

.BEACH FORECAST...
The risk of rip currents is moderate today, but conditions will
continue to improve through Monday. Tuesday onward, the moderate
rip current risk for northern and eastern Puerto Rico will return.
The rip current risk will be low for the Virgin Islands through
the forecast period.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
346 AM AST Sun Apr 13 2025

.SYNOPSIS...
Showers and thunderstorms will continue to develop across the
east, north, west and interior of Puerto Rico, with additional
showers also streaming over the Virgin Islands at times. This will
maintain the threat for urban and small stream flooding elevated
through much of the forecast period. Conditions are expected to
improve on the next weekend. Temperatures will be above normal,
mostly for urban and coastal areas that do not experience the
afternoon rain activity.

&&

.SHORT TERM...Today through Tuesday...

Mostly tranquil conditions prevailed across the islands, under
partly cloudy skies. Passing showers were observed moving over
portions of southeastern and southern Puerto Rico, leaving minimal
accumulations. Minimum temperatures stayed in the mid to upper 70s
in the coastal areas, and in the mid to upper 60s in the mountains.
Winds prevailed from the southeast at 5 to 10 mph.

A weak cold front will continue to move towards the local area
today. As the front approaches the area, additional moisture will
continue to be pulled from the Caribbean waters into the area. The
precipitable water content will remain above-normal across the
region with values up to 2.2 inches through Tuesday. Therefore, the
available moisture in combination with sufficient instability over
the area will enhance the potential to observe the development of
strong showers and thunderstorms each afternoon. Today, the
strongest activity is expected over the interior and northwestern
Puerto Rico. However, winds will begin to shift tonight from the
northeast in response of a surface high pressure moving from the
western to central Atlantic. By Monday, the shower activity is
anticipated to affect the southwestern portions of Puerto Rico after
mid-day. Across the U.S. Virgin Islands, mostly fair weather is
anticipated over the next few days, with passing showers moving into
the area during the morning hours.

For the next several days 925 mb temperatures will be at normal
to above, and also with high humidity levels across the region.
Highs will remain in the upper 80s to low 90s across the coastal
and urban areas, and in the upper 70s to mid 80s in the mountains
and higher elevations. A slight relief in temperatures is expected
on Monday as winds shift from the northeast. Remember to stay
hydrated, wear light clothes, and take breaks in shaded areas!

.LONG TERM...Wednesday through Sunday...

Unsettled weather conditions are expected to continue across the
islands through at least early in the weekend. On Wednesday, a
surface low pressure will develop north of the islands while
moving toward the northeast. This will maintain a steady
southerly wind flow from the surface all the way up into 700 mb.
Then, late on Wednesday and into the end of the week, a polar
trough will move into the western Atlantic. This will weaken the
pressure gradient considerably, with wind speeds falling from
nearly 13 kts on Wednesday, 7 kts on Thursday, and 2-3 kts on
Friday. The winds will gradually shift from the south too, pulling
moisture from the Caribbean into the islands. As a result,
showers will continue to stream at times over eastern and southern
Puerto Rico and the Virgin Islands at times. However, the
strongest activity is anticipated for the interior, western and
northern Puerto Rico in the afternoon and early evening hours. The
main threat will be urban and small stream flooding, rapid river
rises, mudslides and lightning strikes from the thunderstorms.

This trough will also escort a cold front into the region, and it
could cross the island son Saturday, and winds will begin to shift
from the north by then. Plenty of moisture should continue to fire
up convection across the Cordillera Central in the afternoon
hours. After the front crosses the islands, drier air will move
in, with cooler temperatures, breezy conditions and less rain in
forecast.

Before the front moves, from Wednesday through Friday, the
southerly wind flow will cause temperatures to increase, with heat
indices just above 102 degrees for urban and coastal areas. Areas
with a thick cloud layer and frequent showers will see a relief
from these high temperatures.


&&

.AVIATION...
(06Z TAFs)

VFR conds expected across all terminals during the fcst period.
SHRA/TSRA associated with a cold front near the area may cause brief
periods of MVFR conditions at TJSJ and TJBQ through 13/22Z. Mntn
obsc is expected for along the Cordillera Central in the afternoon.
Winds will prevail from the SE at 10-15 kts with stronger gusts,
mainly near the strongest SHRA activity.

&&

.MARINE...
A broad surface high pressure will remain anchored over the central
Atlantic, promoting light to moderate east to southeast winds
through the weekend. However, another surface high pressure will
build over the western Atlantic, pushing a front over the local area
early in the week, promoting moderate to fresh northeast winds.
Shower and thunderstorm activity will develop each day, mainly across
the Atlantic waters and the Mona Passage.

&&

.BEACH FORECAST...
Light winds will maintain the risk of rip currents low today and
on Monday. However, moderate winds return on Tuesday, leading to
moderate risk for northern and eastern Puerto Rico for most of the
workweek. Be aware that afternoon thunderstorms pose a threat of
lightning, mostly for the beaches in the west and north coast of
Puerto Rico.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
447 AM AST Mon Apr 14 2025

.SYNOPSIS...

Showers and thunderstorms will continue to develop each afternoon
across the islands, enhancing the risk for urban and small stream
flooding, as well as mudslides and rapid river rises. Todays
heavy rains will focus over the southwestern quadrant. Other
hazard risks include lightning over the next few days, with non-
thunderstorm wind risks anticipated on Tuesday. The risk of life-
threatening rip currents will rise to moderate by Tuesday for most
north- and east-facing beaches.

&&

.SHORT TERM...Today through Wednesday...

A variable weather pattern prevailed across Puerto Rico and the U.S.
Virgin Islands with cloudy skies and some showers. At around 1 AM,
shower activity moved over the north-central sections of Puerto
Rico. Rainfall accumulations associated with these showers remained
at less than 1 inch, with the highest amounts over Arecibo.
Overnight temperatures remained in the upper 60s to lower 70s across
the mountains and in the upper 70s to lower 80s across the coastal
areas.

Puerto Rico and the U.S. Virgin Islands remain under a moist and
somewhat unstable weather pattern. An approaching frontal boundary
continues to enhance moisture content across the region, with
precipitable water values near or above the 75th percentile, around
1.75 inches. At the surface, a building high-pressure system over
the western Atlantic is producing a northeasterly wind flow,
steering moisture toward the islands. As a result, scattered showers
are expected across windward coastal areas during the morning,
followed by afternoon convection focused over the southwestern
quadrant of Puerto Rico due to local and diurnal effects. Conditions
aloft are modestly unstable, with 500 mb temperatures near -8C
supporting the potential for isolated thunderstorms. By Tuesday, the
high-pressure system will continue to shift eastward across the
Atlantic, allowing surface winds to gradually veer from the
northeast to more easterly. This wind shift, combined with
persistent above-normal moisture levels and relatively steep mid-
level lapse rates, will maintain the potential for scattered to
numerous showers across the region. The best chance for convection
remains during the afternoon across interior and western Puerto
Rico. However, occasional passing showers may also affect the U.S.
Virgin Islands and eastern municipalities during the morning hours.

By Wednesday, the influence of a developing surface trough over
Hispaniola and a broad high-pressure system over the central
Atlantic will result in a southeast wind flow across the region.
This shift will introduce even warmer and more humid conditions. The
southeasterly flow will push tropical moisture, increasing the
potential from an increase in the coverage of showers and isolated
thunderstorms. Once again, the afternoon hours will be the most
favorable for convective development, particularly across interior
and northwestern Puerto Rico. Residents and visitors should remain
alert for periods of locally heavy rainfall and ponding of water in
poor drainage areas.


.LONG TERM...Thursday through Monday...

The overall forecast scenario remains consistent with the previous
discussion. On Thursday, winds will weaken as a polar trough
approaches from the western Atlantic. At the same time, enhanced
moisture from the Caribbean will move over the region, driven by a
southeasterly wind flow. These features will support the development
of showers and thunderstorms, particularly across the interior,
western, and northern portions of Puerto Rico during the afternoon
and early evening hours. The impacts associated with this weather
pattern will be the urban and small stream flooding, rapid river
rises, mudslides, and frequent lightning associated with
thunderstorm activity. Friday will bring similar conditions,
although winds are forecast to gradually veer toward the east. The
approaching trough will be accompanied by a cold front, which is
expected to move into the area by Saturday. As the front crosses the
islands, winds will shift to the northeast, continuing to support
moisture in some afternoon convection, especially over the
Cordillera Central. Widespread showers and isolated thunderstorms
remain likely during this period. By Sunday into Monday, a drier and
cooler air mass is forecast to move into the region in the wake of
the front. This transition will bring breezy northeast winds, lower
humidity, and reduced rain chances, signaling a return to more
stable and seasonable weather conditions.

Overall, unsettled weather conditions are expected to persist across
the local islands through at least Saturday, with gradual
improvement anticipated late in the weekend and into early next week.

&&

.AVIATION...
(06Z TAFs)

VFR to MVFR conditions will be present across the TAF sites during
this period. TSRA and SHRA are expected across TJPS and TJBQ at
14/15Z to 14/20Z, resulting in a lower flying ceiling and reduced
VIS in the TAF site and the vicinity of most sites. Winds will
remain from the NE at 15 mph, with gusty winds near the showers.

&&

.MARINE...

A high pressure system building over the western Atlantic will
promote moderate to locally fresh east to northeast winds over the
next few days. This same feature will push the remnants of a frontal
boundary across the region, leading to increased showers and
thunderstorms. Afternoon convection will also affect portions of the
coastal waters. Any thunderstorm activity will likely generate
locally hazardous marine conditions for small craft.

&&

.BEACH FORECAST...

Light winds will maintain the risk of rip currents low through
early Tuesday. However, increasing winds on Tuesday will lead to
moderate risk for most north- and east-facing beaches. Be aware
that afternoon thunderstorms pose a threat of lightning, mostly
for the beaches in the west and southwestern coast of Puerto
Rico.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
428 AM AST Tue Apr 15 2025

.SYNOPSIS...

We anticipate showers and thunderstorms to develop this afternoon
across west to northwestern PR, enhancing the risk for urban and
small stream flooding, as well as mudslides and rapid river rises.
The remnants of this activity will likely linger through the
evening hours. Other hazard risks include lightning over the next
few days, with non- thunderstorm wind risks anticipated today. The
risk of life- threatening rip currents will be moderate today for
most north- and east- facing beaches. Increasing winds and a
northerly swell will likely deteriorate marine and surf zone
conditions over the weekend.

&&

.SHORT TERM...Today trough Thursday...

Tranquil weather conditions prevailed across the islands during the
night and early morning hours. Radar Doppler showed a few showers
moving inland, but no significant rainfall accumulations were
observed or even expected with this activity. Cloudiness was present
for most of the northeastern section of the island and the U.S.
Virgin Islands. Overnight temperatures were in the low 80s across
coastal regions and much colder in the mountain sections.

From today through Thursday, Puerto Rico and the U.S. Virgin Islands
will remain under a moist and somewhat unstable weather regime. The
global model indicates that precipitable water (PWAT) values will
stay at or above 1.5 inches, remaining above the climatological
median and supporting conditions for frequent passing showers and
afternoon convective activity. Mid- and low-level relative humidity
values, particularly in the 700–500 mb and 850–700 mb layers, will
remain near or above the 50th percentile, indicating a sufficiently
moist column for sustained shower development. Winds will gradually
veer from easterly today to east-southeasterly by Wednesday, helping
to transport fragmented moisture into the region. This pattern
favors passing showers over windward coastal areas during the
morning hours, followed by isolated thunderstorms across interior
and western Puerto Rico in the afternoon.

By Wednesday, the focus of convection will shift toward northwestern
Puerto Rico due to the evolving southeasterly flow and the
development of a surface trough west of the region. Instability
increases as an upper level trough moves more eastward into the
Caribbean, leaving the forecast area under an unstable pattern.
Widespread shower activity is not anticipated due to the lack of
moisture at the low levels, therefore, localized showers across the
western interior and the northwestern section of the island is
expected each afternoon. A warming trend is expected at low levels,
with 925 mb temperatures forecast to remain above the 75th
percentile. This, combined with lingering moisture, will increase
the heat risk across most of the coastal and urban areas, especially
from 10 AM to 4 PM on Wednesday and Thursday.


.LONG TERM...Friday through Tuesday...

Unsettled weather conditions will dominate the forecast area as low
pressure over the north-northwestern Atlantic continues to draw
moisture from the Caribbean. Toward the end of the workweek and into
the weekend, winds are expected to shift gradually from the east-
southeast to the northeast.

The latest model guidance continues to indicate the approach of a
trough accompanied by a cold front, which is expected to move into
the region on Saturday. These features will enhance the potential
for shower and thunderstorm development, particularly across the
interior and southwestern portions of Puerto Rico during the
afternoon and early evening hours. Model data suggests precipitable
water values ranging from 1.8 to 1.9 inches, 500 mb temperatures
between -8 and -9 degrees Celsius, and deep-layer moisture extending
from the surface up to around 500 mb. These conditions will support
the potential for urban and small stream flooding, rapid river
rises, mudslides, and frequent lightning associated with
thunderstorm activity. At this time, Saturday is the wettest day of
the long-term period.

A gradual improvement in weather conditions is anticipated from
Sunday through Tuesday as a drier and cooler air mass is forecast to
move into the region behind the front. This transition will bring
lower humidity and reduced rain chances, signaling a return to more
stable and seasonable conditions. Late Saturday winds will increase
and become breezy through at least Tuesday.

&&

.AVIATION...
(06Z TAFs)

Mostly, VFR conditions will persist for all the TAF sites with some
brief MVFR conditions along the TJBQ, TJPS, and TJSJ at around
15/18Z with the afternoon convection (TSRA and SHRA). Therefore, a
lower ceiling and reduction in VIS are forecasted. Winds will peak
at 15/14Z from the E-ESE up to 15 knots, with gusty winds near the
strongest showers.

&&

.MARINE...
A high pressure system building over the western Atlantic will
promote moderate to locally fresh east to northeast winds, gradually
veering to become easterly tomorrow and east-southeasterly on
Wednesday. This high will push the remnants of a frontal boundary
across the region, leading to increased showers and thunderstorms.
Afternoon convection will also affect portions of the coastal waters.
Any thunderstorm activity will likely generate locally hazardous
marine conditions for small craft. Increasing winds and a northerly
swell will likely deteriorate marine conditions over the weekend.

&&

.BEACH FORECAST...
Increasing winds will lead to moderate risk for most north- and
east-facing beaches, today. Deteriorating marine conditions will
bring the risk of rip currents to high during the weekend. Be
aware that afternoon thunderstorms pose a threat of lightning,
mostly for the beaches in the west and southwestern coast of
Puerto Rico.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
434 AM AST Wed Apr 16 2025

.SYNOPSIS...

Increase instability should remain through the forecast period,
meaning that there is a risk of flooding and lightning over the
next few days. The risk of life- threatening rip currents will
continue moderate for most north- and east- facing beaches.
Increasing winds and a northerly swell will likely deteriorate
marine and surf zone conditions over the weekend.

&&

.SHORT TERM...Today through Friday....

Variable weather conditions prevailed along the local islands with
periods of isolated light to moderate showers across eastern
sections of Puerto Rico. Shower activity remained relatively
localized with minimal rainfall accumulations. Overnight minimum
temperatures were in the low 70s across the mountain areas and in
the upper to lower 80s across the coastal areas.

A subtropical jet will continue to extend eastward into the central
Atlantic, placing Puerto Rico and the U.S. Virgin Islands under an
increasingly unstable atmospheric pattern through Friday, with peak
influence expected on Thursday. This upper-level feature will
enhance divergence aloft, supporting convective development.
Although precipitable water (PWAT) values will generally follow a
seasonal pattern, a slight decrease to around 1.4 inches is expected
later today, followed by an increase to approximately 1.8 inches by
Thursday. Surface winds will remain from the east today, becoming
more southeasterly on Thursday due to an induced surface trough
developing north of Hispaniola. This will promote additional
moisture advection into the region, favoring passing showers,
particularly during the overnight and early morning hours.

GFS model guidance suggests that the induced surface trough will
move into the local area from late Thursday into Friday, weakening
the surface pressure gradient. As a result, lighter winds and
enhanced low-level convergence will increase the potential for
widespread and persistent shower activity. Isolated to scattered
thunderstorms are likely each afternoon over interior and western
Puerto Rico, and across the surrounding waters during the night,
supported by cold 500 mb temperatures ranging between -8°C and -9°C.
Meanwhile, 925 mb temperatures are expected to peak on Friday,
contributing to warmer conditions across the northern coastal areas
of Puerto Rico. Given the anticipated rainfall and slower storm
motion, there is an elevated risk of urban and small stream
flooding, particularly from Thursday afternoon through Friday.


.LONG TERM...Saturday through Wednesday...

The latest model guidance continues to indicate the approach of a
trough accompanied by a cold front, which is expected to move into
the region on Saturday. These features will enhance the potential
for shower and thunderstorm development, particularly across the
interior and southwestern portions of Puerto Rico during the
afternoon and early evening hours. Winds are also forecast to
increase and become breezy through at least Monday as a surface high-
pressure system strengthens over the western Atlantic.

Precipitable water models suggest values between 1.8 and 1.9 inches,
500 mb temperatures ranging from -8 to -9 degrees Celsius, and deep-
layer moisture extending from the surface up to around 500 mb
through the weekend. These conditions will support the potential for
urban and small stream flooding, rapid river rises, mudslides, and
frequent lightning associated with thunderstorm activity. As of now,
the weekend is the wettest part of the long-term period.

A gradual improvement in weather conditions is expected from late
Sunday through Tuesday as a drier and cooler air mass moves into the
region behind the front. This transition will bring lower humidity,
reduced rain chances, and a return to more stable and seasonable
conditions.

&&

.AVIATION...
(06Z TAFs)

VFR conditions will prevail for most of the TAF sites
during the period. Some TSRA and SHRA at the afternoon hours will
result in MVFR conditions across TJBQ and TJSJ at around 16/18Z with
a reduction in VIS and lower ceilings. Winds will pear at 16/15Z
from the east at 15 knots with gusty winds near the strongest
showers.

&&

.MARINE...

A high pressure system building over the western Atlantic will
promote moderate to locally fresh easterly winds, gradually veering
to become east-southeasterly today. This high will continue to push
the remnants of a frontal boundary across the region, leading to
increased showers and thunderstorms across local waters. Any
thunderstorm activity will likely generate locally hazardous marine
conditions, small craft should exercise caution. Increasing winds and
a weak northerly swell will likely deteriorate marine conditions
over the weekend.

&&

.BEACH FORECAST...

Increasing winds will promote a moderate risk for most north- and
east- facing beaches of Puerto Rico and St. Croix in the U.S.
Virgin Islands. These conditions are expected through Thursday,
improving by Friday. However, deteriorating marine conditions
will bring the risk of rip currents to high during the weekend. Be
aware that afternoon thunderstorms pose a threat of lightning,
mostly for the beaches in the west and southwestern coast of
Puerto Rico.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
525 AM AST Thu Apr 17 2025

.SYNOPSIS...
A wet and unstable weather pattern will be present across the
islands today and this weekend. Therefore, residents and visitors
can expect periods of strong showers with thunderstorms,
increasing the potential for urban flooding and minor small-stream
flooding. The heaviest activity will be lightning, with the threat
of lightning present as well. Tranquil marine conditions will
persist and deteriorate for the upcoming workweek.

&&

.SHORT TERM...Today through Saturday...

During the overnight hours, showers affected northwestern and
eastern Puerto Rico, with rainfall accumulations between 0.30 and
0.50 inches. Skies remained partly cloudy across the region, with
overnight temperatures ranging from the low to mid-70s in coastal
areas and the low to mid-60s in the higher elevations. Winds were
generally light and easterly, allowing showers to linger a bit
longer than usual.

The short-term forecast remains on track, with model guidance
continuing to indicate the influence of an upper-level trough and an
induced surface trough over the region. These features will promote
a gradual increase in atmospheric instability and precipitable water
values, which are forecast to remain above normal for this time of
year (between 1.8 and 2.0 inches) through Saturday. Today, winds
will persist from the southeast. Combined with abundant moisture,
this will support a typical pattern of morning showers over eastern
Puerto Rico, followed by afternoon convection over the northwestern
quadrant. On Friday, a weakening pressure gradient will result in
lighter easterly winds, favoring slower-moving and more persistent
showers, which will increase the potential for localized flooding.
By Saturday, winds are forecast to shift and strengthen from the
northeast.

Overall, with the expected moisture and instability in place, the
flood risk will remain elevated through Saturday, especially during
the afternoon hours. Ponding of water on roadways and poorly drained
areas, as well as localized urban and small stream flooding, will be
likely. Isolated to scattered thunderstorms are also possible each
day, mainly over interior and western Puerto Rico in the afternoon
and over surrounding waters during the overnight hours. This
convective activity will be supported by cold mid-level
temperatures, ranging between -8°C and -9°C.

.LONG TERM...Sunday through Thursday...

A wet and unstable weather pattern will be present for the first
part of the long-term period. At the upper levels, 250 MB height
suggests a strong upper-level trough, then converting in a cut-of-
low just north of the CWA, resulting in unstable weather
conditions aloft and colder temperatures at the 500 MB, rounding
between -8 to -10 C degrees. These conditions create a favorable
atmosphere with good potential for intense thunderstorm activity.
At the surface, a building surface high pressure located over the
western Atlantic will increase the pressure gradient across the
region, and more moderate to locally strong winds will be in
place, becoming from the northeast between 15 to 25 mph, with
gusty winds. As a result, residents and visitors can expect windy
conditions with fast-moving shower activity, resulting in less
rainfall accumulation from Sunday into Monday.

Improving weather conditions will be in place from Tuesday
onwards; at the upper levels, the divergence zone of the upper low
moves out of the region. A mid-level ridge will also be in place,
inducing more stable weather conditions. At the surface, the
combination of the surface ridge and the reflected cut of low at
the surface will keep the northeasterly wind flow across the
region. For now, model guidance suggests an amore drying trend;
however, given the proximity of the surface, low pressure,
cloudiness, and moisture are likely across the region during this
period. Therefore, residents and visitors can expect frequent
passing showers along the eastern and northeastern sections of
Puerto Rico and the U.S. Virgin Islands.

&&

.AVIATION...

06Z TAFs)
All TAF sites should experience VFR conditions. However, some
VCTS and SHRA during the afternoon hours could result in MVFR
conditions across TJBQ and TJSJ at around 17/17Z with a reduction
in VIS and lower ceilings. Winds will gradually peak after 17/14Z
from the E-SE up to 15 knots with gusty winds near the strongest
showers.

&&

.MARINE...
A strengthening high-pressure system over the western Atlantic
will maintain moderate to fresh easterly shifting to an east-
southeasterly direction today. This setup will help transport the
remnants of a dissipating frontal boundary across the area,
resulting in an uptick in shower and thunderstorm activity,
especially over the local waters. Thunderstorms may lead to
localized hazardous marine conditions, prompting small craft
operators to exercise caution. Additionally, the combination of
increasing winds and a weak northerly swell will contribute to
worsening marine conditions heading into the weekend.

&&

.BEACH FORECAST...

Moderate easterly winds will raise the risk of rip currents along
most north- and east-facing beaches of Puerto Rico and St. Croix.
Deteriorating seas over the weekend are expected to elevate the
rip current risk once again. Beachgoers should also remain alert
to the threat of afternoon thunderstorms, particularly along the
western and southwestern shores of Puerto Rico, which may produce
dangerous lightning.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
435 AM AST Fri Apr 18 2025

.SYNOPSIS...

An induced surface trough and plenty of moisture will result in a
wet and unstable weather pattern today through this weekend.
Therefore, periods of strong showers with thunderstorms will
increase the potential for urban flooding and minor small-stream
flooding. The heaviest activity will be lightning, with the threat
of lightning present as well. Tranquil marine conditions will
persist and deteriorate for the upcoming workweek.

&&

.SHORT TERM...Today through Sunday...

Overnight, showers affected Puerto Rico and the U.S. Virgin Islands,
with the heaviest rainfall and thunderstorm activity occurring over
the Atlantic waters, prompting the issuance of a Marine Weather
Statement. Rainfall accumulations over land ranged from 0.10 to
approximately 1.90 inches, with the highest values observed across
some northern municipalities like Manati, Vega Baja, and Camuy,
as well as other southwestern municipalities like Yauco.
Temperatures remained in the mid to upper 70s in coastal areas and
into the upper 60s to low 70s in the higher elevations as mostly
cloudy skies prevailed. Winds were light and variable, which
contributed to the persistence of showers across the islands.

The forecast remains on track with a mid-to-upper-level trough
approaching from the west, which is expected to linger through the
weekend. Precipitable water values are forecast to remain around
1.85 inches or higher (above climatological normals for this time of
year). While the most active portion of the trough will stay to the
north and northeast of the region, an active weather day is still
expected today into Saturday. Today, showers and thunderstorms will
likely develop over the interior of Puerto Rico and spread outward,
supported by diurnal heating and sea breeze convergence, promoting
an unstable and moist pattern. However, activity is expected to
taper off as the weekend progresses gradually. With the surface
trough axis moving overhead today, wind speeds will decrease
significantly. This will lead to slow-moving showers, increasing the
potential for heavy rainfall accumulations, urban and small stream
flooding, rapid river rises, and even isolated flash flooding or
landslides, particularly in vulnerable and steep terrain.

By Saturday, winds will shift and strengthen from the northeast.
This change will promote faster-moving showers, which should help
limit rainfall totals and lead to more localized impacts.

A gradual improvement in weather conditions is anticipated by Sunday.


.LONG TERM...Monday through Friday...

An unsettled and moist weather pattern will prevail at the
beginning of the workweek. On Monday, upper-air analysis indicates
a pronounced trough evolving into a cut-off low just north of the
forecast area. This synoptic feature will induce significant
instability, as reflected in model-derived 500 MB temperatures
dropping between -8°C and -10°C, which is supported by the latest
TJSJ RAOB and GFS analysis. This colder air aloft will promote
robust convective development and increase the potential for
thunderstorm activity across the region, particularly over interior
and western Puerto Rico during the afternoon hours. At the
surface, a strengthening Atlantic high will enhance the local
pressure gradient, with 925 MB wind speeds peaking between 15 to
25 knots and occasional gusts above that range, according to GFS
guidance. Winds will shift from the northeast, resulting in breezy
to windy conditions and advecting fast-moving showers across the
northern and eastern municipalities of Puerto Rico, as well as the
U.S. Virgin Islands. However, given the enhanced steering flow,
rainfall totals are expected to be limited from late Sunday into
Monday despite periods of active weather. Additionally, both
700–500 MB and 850–700 MB relative humidity values exceed the 75th
percentile, suggesting a deeply saturated column and increased
potential for vertically developed convection during this period.

From Tuesday through Friday, weather conditions are expected to
gradually improve. The upper-level divergence zone tied to the
cut-off low will migrate eastward, allowing for the development of
a mid-level ridge that will introduce drier and more stable air
masses over the region. The global model shows a notable drop in
PWAT values, reaching below 1.0 inch by Sunday, indicative of a
more suppressed convective environment. Despite this drying trend,
residual cloudiness and embedded moisture from the proximity of
the lingering surface low may still bring passing showers,
especially across eastern Puerto Rico and the U.S. Virgin Islands
under continued northeasterly trade winds.
&&

.AVIATION...
(06Z TAFs)

VFR conditions across all TAF sites. However, we forecast an
increase in shower and thunderstorm activity today, which could
result in MVFR conditions across TJPS and TJSJ after 18/15Z with a
reduction in VIS and lower ceilings. E-SE from 6 to 10 knots with
slightly higher gusts near the heaviest rainfall activity should
prevail. After 18/18Z, winds will gradually become from the E-NE and
peak by tomorrow.

&&

.MARINE...

An induced surface trough and a broad surface high pressure over
the central Atlantic will promote light southeasterly winds across
the region from today into tomorrow. By Sunday, increasing
surface winds due to another surface high pressure over the
western Atlantic will result in wind-driven seas between 6 to 7
feet, enhancing choppy marine conditions along the area.
Thunderstorm activity will be present across the local waters
today into Sunday due to strong showers and thunderstorms,
resulting in localized hazardous marine conditions. &&

.BEACH FORECAST...

A low risk of rip currents is expected across all coastal areas
today. However, the risk will increase to moderate on Sunday and
become high by Sunday afternoon and into the upcoming workweek due
to strengthening winds. Moderate easterly winds will raise the rip
current threat along most north- and east-facing beaches of Puerto
Rico and St. Croix. Additionally, deteriorating marine conditions
over the weekend will further elevate the hazard. Beachgoers
should also remain vigilant for afternoon thunderstorms,
especially along the western and southwestern coasts of Puerto
Rico, where dangerous lightning may occur.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
529 AM AST Sat Apr 19 2025

.SYNOPSIS...

The combination of a mid-to-upper-level trough and surface-
induced trough, as well as available moisture, will continue to
promote a moist and unstable pattern during this weekend.
Therefore, periods of strong showers with thunderstorms will
promote an elevated potential for urban flooding and minor small-
stream flooding. Marine and coastal conditions will also
deteriorate with a Small Craft Advisory starting this evening for
the offshore Atlantic waters, and a High Risk of Rip Currents
starting tomorrow for the north-oriented beaches of Puerto Rico.

&&

.SHORT TERM...Today through Monday...

Radar and satellite data indicated an increase in shower activity
overnight, driven by low-level moisture convergence under
northeasterly trade winds. The most active areas included the
northern and eastern half of Puerto Rico, Culebra, and the northern
U.S. Virgin Islands. Since 8 PM AST, radar estimates suggest peak
rainfall totals of about half an inch across portions of north-
central and far eastern Puerto Rico. Temperatures overnight ranged
from around 60°F in the higher elevations of the Cordillera Central
to the mid-70s across eastern Puerto Rico and the U.S. Virgin
Islands. Winds were generally from the north to northeast at 5–15
mph along windward areas, while remaining light and variable across
southern and interior sections.

A mid-to-upper-level trough, in combination with a surface-induced
trough, will continue to dominate the regional weather pattern,
fostering a persistently unstable and moist atmosphere favorable for
deep convective development through Sunday and sustaining the
potential for increased showers and thunderstorms. The environment
will feature a weak or nearly absent trade wind cap inversion,
promoting vertical cloud growth. At the same time, mid-level
temperatures will remain unusually cool—with 500 mb values dipping
to around -10°C between today and Saturday—further enhancing
instability. This setup, combined with persistent low-level moisture
convergence, will support efficient rainfall processes, with
precipitable water values ranging from 1.8 to 2.0 inches, well above
normal for this time of year.

A significant transition in the weather pattern is anticipated by
late Sunday into Monday. A drier air mass will quickly filter into
the region, accompanied by increasing convergence and subsidence
aloft, associated with the trough's trailing side. This will lead to
less favorable conditions for deep convection and promote a more
stable atmosphere. As a result, a notable decrease in shower and
thunderstorm activity is expected to start the new workweek.

Given the current setup, there is an elevated risk of flooding,
particularly in areas that experience persistent or repeated rounds
of convection through late tonight. Urban locations, poor drainage
areas, and regions with already saturated soils are especially
vulnerable. Localized flash flooding cannot be ruled out. Additional
hazards include lightning strikes and strong thunderstorm winds. For
more information on potential weather hazards, refer to the
Experimental Graphical Hazardous Weather Outlook at:
https://www.weather.gov/erh/ghwo?wfo=sju.

.LONG TERM...Tuesday through Saturday...

Current model guidance has precipitable water values (PWAT) at 1 to
1.20 inches to start the long term period, gradually increasing as
we continue into the period. To start the period, a mid to upper
level trough will be northeast of the islands, gradually
deteriorating as we head in to the midweek. A surface trough,
however, will continue to cross the region, promoting east-
northeasterly steering flow on Tuesday, gradually backing to
become southeasterly by Wednesday. An more east-southeast Thursday
and into the weekend. A notable increase in PWAT values is
forecast by late Thursday, with most of the region having more
than 1.5 inches of PWAT, with the eastern region having around 2.0
inches. By late Saturday, current model guidance has most of the
region at around 2.0 inches (above normal values for this time of
the year). Most available moisture will be confined to below 700
mb through at least late Friday. In general, weather conditions
are forecast to gradually improve during the start of the next
workweek, overnight and morning showers are still forecast over
windward areas while afternoon convection will still occur over
sectors of western PR, with exact locations depending on the
prevalent steering flow that day. The increase in moisture to end
the workweek and into the next weekend can increase the coverage
of this activity. 925 mb temperatures are forecast to be at below
to normal values to start the period, gradually climbing due to
east-southeast flow during the second half of the workweek.

&&

.AVIATION...
(06Z TAFs)

SHRA/TSRA will likely cause brief MVFR conditions at all TAF sites,
with the most significant impacts at TJSU, TJBQ, and USVI terminals
through the period and at TJPS, mainly between 19/16Z–23Z. Winds
from the northeast will range from 5–15 knots, increasing to 10–20
knots with higher gusts after 19/14Z. Gusty winds near showers and
storms are possible. Winds will gradually ease to 5–10 knots by
19/23Z.

&&

.MARINE...

A surface high pressure system over the western Atlantic will
continue to push remnant showers of a past frontal boundary across
the region over the next few days while a nearby mid to upper level
trough and a surface trough produces favorable conditions for their
development. This will lead to increased showers and thunderstorms
across the local waters. Increasing northeasterly winds and a weak
northerly swell will deteriorate marine conditions by this evening
and into early next week. A Small Craft Advisory is in effect for
the offshore Atlantic Waters.

&&

.BEACH FORECAST...

A low to (in some areas of north-central and northwestern PR)
moderate risk of rip currents is expected today. Tonight, the
risk increases to moderate for all north-oriented beaches of
Puerto Rico. Life-threatening rip currents often occur in the
vicinity of groins, jetties, reefs, and piers.

For tomorrow, Sunday, increasing winds and a weak northerly swell
will further deteriorate coastal conditions. A High Risk of Rip
Currents is forecast for the north-oriented beaches of Puerto
Rico, from Rincon to Fajardo, through at least early Tuesday. A
High Risk of Rip Currents means that life-threatening rip
currents are likely in the surf zone.

If you become caught in a rip current, yell for help. Remain
calm, do not exhaust yourself and stay afloat while waiting for
help. If you have to swim out of a rip current, swim parallel to
shore and back toward the beach when possible. Do not attempt to
swim directly against a rip current as you will tire quickly.

Beachgoers should also remain vigilant for afternoon thunderstorms,
especially along the western and southwestern coasts of Puerto
Rico this weekend, where dangerous lightning may occur.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
411 AM AST Sun Apr 20 2025

.SYNOPSIS...

An increased flood risk continues this morning, especially in
areas with saturated soils, mainly across northern and central
Puerto Rico. Mid-to-upper-level and surface-induced troughs will
continue to dominate through early this afternoon, maintaining
favorable conditions for shower and t-storm development. A
significant pattern shift begins later this afternoon and tonight
as a drier air mass moves in. Marine and coastal conditions are
also deteriorating. Small Craft Advisories are, or will soon be,
in effect for the offshore Atlantic waters, the Mona Passage & the
nearshore waters of N and NW Puerto Rico. A High Risk of Rip
Currents is in effect today for the north-oriented beaches of
Puerto Rico, from Rincon to Fajardo, and Culebra.

&&

.SHORT TERM...Today through Tuesday...

Radar and satellite data revealed an active 18–24 hours, driven
by a mid-to-upper-level trough interacting with a surface trough.
Widespread showers and thunderstorms developed under moist
conditions and north-northeasterly trade winds. The heaviest
rain—up to 8.3 inches—fell over parts of Vega Baja, Manati,
Morovis, and Ciales, with another peak near the Corozal-Orocovis
line. This led to minor to moderate river flooding and road
closures along the Rio Grande de Manati and Rio Cibuco. Multiple
Flood Advisories and Warnings were issued. Overnight lows ranged
from 60°F in the mountains to the mid-70s in eastern PR and the
USVI, with light to moderate N-NE winds.

The mid-to-upper-level and surface-induced troughs will continue
to dominate through early this afternoon, keeping conditions moist
and unstable with a high chance of showers and thunderstorms.
Strengthening north to northeasterly winds, driven by a surface
high to the west-northwest, will enhance moisture advection and
increase trade wind showers. A weak or absent trade wind cap will
support vertical cloud growth, while unusually cool mid-level
temperatures (around -8 to -9°C) will sustain instability. Despite
a gradual drop in precipitable water, values between 1.4 and 1.6
inches will continue to support efficient rainfall.

A significant pattern shift begins later this afternoon and
tonight as a drier air mass moves in, driven by increased
convergence and subsidence aloft behind a departing trough.
Precipitable water may drop to 0.9 inches by Monday, while rising
500 mb temps (near -5°C) and a redeveloping trade wind cap will
stabilize the atmosphere and limit convection. As a result,
expect fewer showers, breezy conditions, and cooler-than-normal
temperatures to start the week, supported by persistent N-NE
winds and lower 925 mb temps.

An increased flood risk continues this morning, especially in
areas with saturated soils—mainly across northern and central
Puerto Rico. Localized flash flooding, lightning, gusty winds,
and non- thunderstorm wind hazards are possible. See the
Experimental Graphical Hazardous Weather Outlook for details:
https://www.weather.gov/erh/ghwo?wfo=sju.

.LONG TERM...Wednesday through Sunday...

Current model guidance has precipitable water values (PWAT) at
0.90 to 1.10 inches by midweek, below normal values. By Wednesday,
the mid to upper level trough that has been affecting the islands
will be well northeast of the islands, and will gradually
dissipate by Thursday. A surface trough, however, will continue to
move towards the islands and eventually cross the region,
promoting east- northeasterly steering flow on Wednesday,
gradually backing to become east-southeasterly by Thursday and
into the weekend. A notable increase in PWAT values is forecast by
early Friday as abundant moisture from the starts to enter the
region behind the surface trough. By Friday morning, eastern PR is
forecast to have more than 1.5 inches of PWAT, with values
gradually increasing eastward and St. Croix having around 2.0
inches. This moisture surge will continue into the weekend with
PWAT values ranging from 1.8 to 2.0 inches by Sunday, above normal
values for this time of the year. Most available moisture will be
confined to below 700 mb to start the period and through at least
late Friday. In general, weather conditions are forecast to
become increasingly more humid as the workweek progresses.
Overnight and morning showers are still forecast over windward
areas while afternoon convection will still occur over sectors of
western PR, depending on the prevalent steering flow each day. The
increase in moisture to end the workweek and into the next
weekend can increase the coverage of this activity. 925 mb
temperatures are forecast to be at below to normal values by
midweek, gradually climbing due to east-southeast flow during the
second half of the workweek.

&&

.AVIATION...

(06Z TAFs)

SHRA/Iso TSRA will likely cause brief MVFR to IFR conditions at all
TAF sites, with the most significant impacts at TJSU, TJBQ, and USVI
terminals through the next 12 hours. VFR conds expected after
20/20Z. Northeast winds at 10–15 knots, increasing to 15–20 knots
with higher gusts after 20/14Z. Gusty winds near showers and storms
are possible. Winds will gradually ease to 5–15 knots by 20/23Z.

&&

.MARINE...

A surface high pressure system over the western Atlantic will
continue to push remnant showers of a past frontal boundary across
the region while a nearby mid to upper level trough and a surface
trough produces favorable conditions for their development this
morning. This will lead to increased showers and thunderstorms
across the local waters. Increasing northeasterly winds and a
weak northerly swell will maintain hazardous marine conditions
into early next week.

A Small Craft Advisory is in effect for the offshore Atlantic
Waters, Mona Passage, and coastal waters of northern and
northwestern Puerto Rico. Conditions will be hazardous to small
craft in these areas. Inexperienced mariners, especially those
operating smaller vessels, should avoid navigating in hazardous
conditions. For more information, please refer to the latest
Marine Weather Message (MWWSJU) & Coastal Waters Forecast
(CWFSJU).

&&

.BEACH FORECAST...

Today, increasing winds and a weak northerly swell will deteriorate
coastal conditions mainly at the northern coasts of Puerto Rico
and Culebra. A High Risk of Rip Currents is in effect for the
north- oriented beaches of Puerto Rico, from Aguadilla to Fajardo,
through at least early Tuesday. A High Risk of Rip Currents is
also in effect for the beaches of Rincon, Aguada and Culebra,
through at least early tomorrow, Monday. A High Risk of Rip
Currents means that life-threatening rip currents are likely in
the surf zone.

A moderate risk of rip currents continues today and tonight for
several beaches of St. Thomas, St. John, St. Croix, SW Puerto
Rico and Vieques. A moderate risk of rip currents means that
life- threatening rip currents are possible in the surf zone. Life-
threatening rip currents often occur in the vicinity of groins,
jetties, reefs, and piers.

If you become caught in a rip current, yell for help. Remain
calm, do not exhaust yourself and stay afloat while waiting for
help. If you have to swim out of a rip current, swim parallel to
shore and back toward the beach when possible. Do not attempt to
swim directly against a rip current as you will tire quickly.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
511 AM AST Mon Apr 21 2025

.SYNOPSIS...

A drier weather pattern is expected today, as a dry air mass
continues to filter in, supported by subsidence behind a departing
upper-level trough, along with strengthening north to
northeasterly winds. Expect fewer showers, breezy conditions, and
below-normal temperatures to start the week. Moisture will
increase again Friday into next week. Small Craft Advisories are
in effect for the Atlantic waters & Mona Passage. A High Risk of
Rip Currents is in effect today for the north- oriented beaches of
Puerto Rico, from Rincon to Fajardo, Culebra, St. Thomas & St.
John.

&&

.SHORT TERM...Today through Wednesday...

Radar and satellite imagery indicated a patch of moisture, carried
by breezy north-northeast winds, producing scattered showers
overnight. The highest radar-estimated rainfall totals, ranging from
0.25 to 0.40 inches, were observed in parts of the north-central,
northeastern, and eastern interior regions of Puerto Rico. A few
isolated showers also affected Vieques, Culebra, and the U.S. Virgin
Islands. Overnight temperatures ranged from the upper 50s in the
mountains to the mid-70s across eastern Puerto Rico and the U.S.
Virgin Islands, with light to moderate N-NE winds along windward
areas and light and variable winds elsewhere.

A significantly different weather pattern is expected today, much
drier than in recent days, as a dry air mass continues to filter in,
supported by subsidence behind a departing upper-level trough.
Although strengthening north to northeasterly winds—driven by a
surface high to the west-northwest—will promote some low-level
moisture advection, precipitable water values will continue to drop,
falling well below climatological normals for this time of year,
reaching approximately 0.8 to 1.0 inches by this afternoon. At the
same time, rising 500 mb temperatures (around -5°C) and re-
establishing trade wind inversion will further stabilize the
atmosphere and suppress deep convection. As a result, expect fewer
showers, breezy conditions, and below-normal temperatures to start
the week, supported by persistent north-to-northeasterly flow and
cooler 925 mb temperatures.

On Tuesday, a slight increase in moisture—reaching around 1.2
inches, still below seasonal averages—will lead to a modest uptick
in afternoon shower activity, though no flooding is expected.
Conditions will turn slightly drier again on Wednesday, though not
as dry as today, with isolated to scattered showers possible during
the afternoon. Importantly, moisture previously associated with the
frontal boundary that affected the region in recent days is expected
to return late Wednesday night, moving in from the east and steered
by east-southeasterly trade winds. This moisture will linger over
the area through the latter part of the week and into the weekend.
Gusty winds and non-thunderstorm wind hazards are today's primary
concerns, especially across exposed and coastal areas. No flooding
is expected at this time. For more information, refer to the
Experimental Graphical Hazardous Weather Outlook:
https://www.weather.gov/erh/ghwo?wfo=sju.

.LONG TERM...Thursday through Monday...

Current model guidance has a pocket of dry air early Thursday,
with precipitable water (PWAT) values ranging at 0.80 to an inch
over the islands, below normal values for this time of the year. A
surface trough should start to cross the islands by this time,
ultimately resulting in east-southeasterly steering flow through
most of the period. Behind this feature is abundant moisture,
weather conditions are forecast to become increasingly more humid
as the workweek progresses. A notable increase in PWAT values is
forecast by early Friday as the aforementioned abundant moisture
from the east starts to enter the region. By Friday morning,
eastern PR is forecast to have more than 1.5 inches of PWAT, with
values gradually increasing eastward and St. Croix having around
1.9 inches. This moisture surge will continue into the weekend
with PWAT values ranging from 1.8 to 2.0 inches by Sunday and
Monday, well above normal values for this time of the year. Most
available moisture will be confined to below 800 mb on Thursday
and early Friday, deepening afterwards. Showers and possible
t-storms are forecast over windward areas while afternoon
convection affects sectors of W-NW PR. Although this activity is
forecast to be shallow on Thursday, the increase in moisture and
more favorable conditions to end the workweek into early next week
can increase the coverage and intensity of this activity and
promote a limited to elevated flooding risk over the islands. 925
mb temperatures are forecast to gradually climb to normal and
above normal values due to the east-southeast flow.

&&

.AVIATION...

(06Z TAFs)

Brief periods of MVFR conditions are expected at TJSJ, TJBQ, and
USVI terminals due to passing showers through 21/14Z and again after
21/23Z. North-northeast winds at 10–15 knots, increasing to 15–20
knots with higher gusts after 21/14Z, then gradually easing to 10–15
knots after 21/23Z. At TJPS, light and variable early winds increase
to 10–15 knots between 21/13–22Z, before returning to light and
variable after 21/22Z.

&&

.MARINE...

A surface high pressure system over the western Atlantic will
continue to push remnant showers of a past frontal boundary across
the region while a nearby mid to upper level trough and a surface
trough moves away from the area. Increasing northeasterly winds and
pulses of northerly swell will maintain hazardous marine conditions
into mid-week.

A Small Craft Advisory is in effect for the offshore Atlantic
Waters, Mona Passage, and coastal waters of northern and
northwestern Puerto Rico, as well as the northern coastal waters
of Culebra, St. Thomas & St. John. Conditions will be hazardous
to small craft in these areas. Inexperienced mariners, especially
those operating smaller vessels, should avoid navigating in
hazardous conditions. For more information, please refer to the
latest Marine Weather Message (MWWSJU) & Coastal Waters Forecast
(CWFSJU).

&&

.BEACH FORECAST...

Today, increased winds and a weak northerly swell is deteriorating
coastal conditions mainly at the northern coasts of Puerto Rico,
Culebra, St. Thomas and St. John. A High Risk of Rip Currents is
in effect for the north- oriented beaches of Puerto Rico, from
Aguadilla to Fajardo, through at least early Wednesday. A High
Risk of Rip Currents is also in effect for the beaches of Rincon,
Aguada and Culebra, through at least early tomorrow, Tuesday. A High
Risk of Rip Currents is also in effect for the beaches of St.
Thomas and St. John, through at least this evening.A High Risk
of Rip Currents means that life-threatening rip currents are
likely in the surf zone.

A moderate risk of rip currents continues today and tonight for
several beaches of St. Croix, SW Puerto Rico and Vieques. A
moderate risk of rip currents means that life-threatening rip
currents are possible in the surf zone. Life-threatening rip
currents often occur in the vicinity of groins, jetties, reefs,
and piers.

If you become caught in a rip current, yell for help. Remain
calm, do not exhaust yourself and stay afloat while waiting for
help. If you have to swim out of a rip current, swim parallel to
shore and back toward the beach when possible. Do not attempt to
swim directly against a rip current as you will tire quickly.

For more information, please refer to the latest Coastal Hazard
Message (CFWSJU) & Surf Zone Forecast (SRFSJU).

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
444 AM AST Tue Apr 22 2025

.SYNOPSIS...

Hazardous marine conditions and life-threatening rip currents
remain the main weather threats today, particularly across the
Atlantic waters and Mona Passage, as well as north-facing
beaches. Fair and stable weather will persist through midweek, but
a shift toward a wetter pattern is expected by the end of the
workweek into the weekend, bringing increased chances of showers
and thunderstorms. Warmer-than-normal temperatures, combined with
rising moisture and atmospheric instability, will elevate the
risk of flooding, especially from Friday through the weekend.


&&

.SHORT TERM...Today through Thursday...

Current satellite derived precipitable water (PWAT) values indicate
around 1.2 inches over the islands, below normal values for this
time of the year. Since midnight, radar estimated rainfall
accumulations show around 0.2 inches over some isolated sectors of
northern PR but overall show none to minimal accumulations over most
of the islands. Lows ranged from the upper 50s at higher elevations
of Puerto Rico and in the the upper 60s to low 70s over the rest of
the interior to southern half of PR. Lows were in the low to mid 70s
across the northern, NW and NE coastal areas of PR, as well as
across Vieques, Culebra and the U.S. Virgin Islands.

A drier air mass, currently northeast of the area, is forecast to
filter in later today, prompting PWAT values at or below 1 inch over
mainly the eastern region. Below normal PWAT values will persist
over most of the short term period. Steering flow will be north-
northeast to start the period but will gradually veer during the
short term period, eventually becoming east-southeasterly on
Thursday as a weak surface trough moves over the region. Breezy wind
risks will also decrease today as winds veer. It is not until late
Wednesday night and Thursday morning that a surge in moisture
(moisture from a past frontal boundary) from the east will increase
PWAT values over St. Croix to 1.5 inches, at normal values for this
time of the year. By Thursday night, this surge in moisture will
increase PWAT values over easternmost PR and the USVI to between 1.5
to 1.7 inches. In the upper levels the mid to upper trough that
affected us during the weekend is currently northeast of the region,
this feature will continue to move away from the region. Overall
generally stable conditions with a trade wind inversion and 500 mb
temperatures at -5 to -6 degrees Celsius will inhibit any deep
convection today and through most of the period. Most available
moisture will be confined to below 800 mb, with drier air above.

Local effects will still result in limited afternoon convective
showers, mainly over southern PR today, southwestern PR tomorrow and
northwestern PR on Thursday. Flooding risks are none to minimal.
Advective showers will continue to affect windward sectors at times
as patches of low-level moisture reach the islands in the form of
isolated to scattered showers. 925 mb temperatures are forecast to
be below normal today, gradually climbing to normal values during
the rest of the period.

.LONG TERM...Friday through Monday...

The long-term forecast indicates a warm, wet, and marginally
unstable weather pattern. Easterly winds will continue to
transport tropical moisture into the region, while a mid-to-upper-
level trough and associated jet streak will enhance conditions
favorable for thunderstorm development. A weakened trade wind
inversion and typical temperatures at 500 mb will further support
instability. Additionally, temperatures are expected to exceed normal
thresholds, particularly in coastal and urban areas, leading to
slightly elevated perceived temperatures. These warmer-than-normal
conditions will further contribute to the overall instability and
potential for heavy rainfall.

Precipitable water values are expected to rise from around 1.5
inches on Friday to over 1.7 inches by Saturday evening,
indicating well-above-normal moisture levels. This, combined with
marginal instability, daytime heating, and above-normal
temperatures, will support the development of afternoon and early
evening showers and thunderstorms. The latest guidance suggests
that Monday will likely be the wettest day of the forecast period, with
moderate confidence in this trend, though the exact timing and
intensity of rainfall and convection remain uncertain and may
shift with future updates. As moisture increases, so does the risk
for moderate to heavy rainfall, which could lead to urban and
small stream flooding, especially in areas prone to frequent
afternoon convection. Additionally, localized flash flooding,
mudslides, and water surges along rivers and tributaries remain a
concern.

With forecast uncertainty still present, it’s important to
monitor future updates closely. Conditions are favorable for
another active weather weekend, with potential impacts that may
evolve as new guidance becomes available.


&&

.AVIATION...
(06Z TAFs)

VFR conditions will prevail throughout the forecast period. Winds
are will start from the NNE this morning, gradually veering to
become ENE. Speeds will be at 10-15 knots, with higher gusts and sea
breeze variation after 22/14Z, decreasing after 22/23Z. VCSH
possible for TJBQ/TJSJ/TISX/TIST during the period and for TJPS
during the early morning and afternoon.


&&

.MARINE...

A surface high over the western Atlantic and a low northeast of
the region will bring moderate northeast winds today, combined
with a weak northeasterly swell, maintaining hazardous marine
conditions through this evening. Small Craft Advisories are in
effect for the offshore and coastal Atlantic waters of Puerto Rico
and the U.S. Virgin Islands, as well as the Mona Passage. Winds
will become light and variable on Wednesday and Thursday as the
low weakens, with easterly winds returning by the end of the
workweek.


&&

.BEACH FORECAST...

Rough to hazardous seas will continue to pose a high risk of life-
threatening rip currents along the northern coasts of Puerto Rico
through late tonight. While the rip current risk will decrease
starting Wednesday, life-threatening rip currents remain possible
at most north-facing beaches. These currents are particularly
dangerous near groins, jetties, reefs, and piers. For more
information, refer to the Coastal Hazard Message (CWFSJU) and the
Surf Zone Forecast (SRFSJU).

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
410 AM AST Wed Apr 23 2025

.SYNOPSIS...

Fair weather will continue today and Thursday, with limited shower
activity. However, increased moisture and instability will bring
wetter, more unsettled conditions starting late Thursday into
Friday, with more showers, isolated thunderstorms, and localized
flooding expected through the weekend and into early next week.
Warmer-than-normal temperatures are likely today and Thursday, and
possibly again on Sunday and Monday. Easterly winds will
contribute to these conditions. At the coast, a moderate rip
current risk will persist, with the risk rising to high on
Saturday due to a weak northerly swell. Stay informed by following
us on social media and checking the Experimental Graphical Hazard
Weather Outlook.


&&

.SHORT TERM...Today through Friday...

Current satellite derived precipitable water (PWAT) values indicate
around 0.87 to 1.15 inches over the islands, below normal values for
this time of the year. Since midnight, radar estimated rainfall
accumulations show around 0.46 inches over Dorado but overall
minimal accumulations over northern municipalities of Puerto Rico.
Official and unofficial stations reported overnight lows from the
upper 50s to low 60s at higher elevations of Puerto Rico and in the
the upper 60s to low 70s over most lower elevations of Puerto Rico,
and the U.S. Virgin Islands. ASCAT winds report generally light to
moderate northeasterly to east-northeasterly surface flow, with the
stronger winds that affected us earlier in the week now over the
western Mona Passage and the Dominican Republic.

PWAT values of 0.8 to 1.25 inches are forecast to remain over the
islands through at least Thursday afternoon, as a drier air mass
remains over the area. Most available moisture will be confined to
below 800 mb through Friday, as we remain under the subsidence side
of a deep layer low to our northeast. Winds will veer to become east
to southeast on Thursday as a surface trough moves in from the east.
This trough will bring in a surge in moisture, starting from the
southeast, on Thursday and Friday. Current model guidance has St.
Croix surpassing 1.5 inches of PWAT, normal values for this time of
the year, by Thursday afternoon. By Friday morning, this surge in
moisture will increase PWAT values over easternmost PR and the USVI
to between 1.5 to 1.7 inches. By this time, southeasterly flow will
prevail. By Friday night, most of the islands will be above 1.5
inches of PWAT while easternmost PR and the USVI reach 1.8 inches,
above normal values for this time of the year.

Overall generally stable and dry conditions will persist today, with
Thursday being a transition day to a wetter end of the week. Local
and diurnal effects will still result in limited afternoon
convective showers, mainly over the interior and W/SW PR today, and
northwestern PR on Thursday. Advective showers will continue to
affect windward sectors at times as patches of low-level moisture
reach the islands in the form of isolated to scattered showers.
Under more favorable conditions and increased moisture, expect a
stronger version of this pattern on Friday, with a limited excessive
rainfall risk as chances moderate to heavy rainfall with t-storms
increases. 925 mb temperatures are forecast to be below normal to
normal today, gradually climbing to normal values and above during
the period as southeasterly flow establishes itself.

.LONG TERM...Saturday through Tuesday...

Model guidance indicates a persistently wet and unstable pattern
through early next week. Deep tropical moisture will stream into
the region, with Precipitable Water (PWAT) values well above
climatological thresholds, ranging from around 1.7 inches on
Saturday morning to about 2.2 inches by Monday morning. A mid-to-
upper-level trough and associated jet streak will enhance lift
and divergence aloft, creating favorable conditions for
thunderstorm development. While 500 mb temperatures will remain
near normal for most of the period, a notable dip to around -9°C
by Monday night into Tuesday will increase upper-level
instability, supporting deeper convection.

At the surface, easterly winds will dominate, gradually shifting
from a southeasterly flow on Sunday and Monday to a northeasterly
flow by Tuesday. This evolving wind pattern will lead to warmer-
than-normal temperatures during the weekend and early next week,
particularly in coastal and urban areas. A cooling trend is
expected to begin on Tuesday.

Flooding risk will persist throughout the forecast period. Monday
and Tuesday are likely the wettest days, bringing the highest
potential for moderate to heavy rainfall and localized flooding,
especially in urban, low-lying, and mountainous areas. While exact
rainfall amounts and timing may vary, confidence in this wet
pattern remains moderate. Given the potential for impactful
weather, users should follow forecast updates as conditions
evolve, particularly heading into the weekend.


&&

.AVIATION...
(06Z TAFs)

Mainly VFR conditions expected to prevail during the period. Winds
from the ENE gradually veering to become E, at 8 to 13 knots, with
higher gusts and sea breeze variations after 23/14Z, decreasing
after 22/23Z. VCSH possible across windward areas and over
Coridillera during the afternoon.


&&

.MARINE...

As the low weakens and dissipates to the north, light and variable
winds will prevail through Friday, with moderate easterly winds
returning by Friday night into Saturday. Overall conditions should
remain favorable for small craft, though localized hazardous
marine conditions may develop near showers and thunderstorms,
which are expected to become more active by the end of the week.


&&

.BEACH FORECAST...

Rip current risk will decrease today but remain moderate along
most north- and east-facing beaches over the next few days,
meaning life-threatening conditions are still possible. Even where
risk is lower, rip currents near groins, jetties, reefs, and piers
can be dangerous. By Saturday, a weak northerly swell will
increase the risk to high. Check the Coastal Hazard Message
(CWFSJU) and Surf Zone Forecast (SRFSJU) for the latest info.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
455 AM AST Thu Apr 24 2025

.SYNOPSIS...

Mostly fair weather will continue this morning followed by showers
mainly affecting interior portions of Puerto Rico during the
afternoon hours. Increased moisture and instability will bring a
more unsettled and wetter weather pattern at the end of the week
into early next week. A moderate rip current risk will persist
along the northern and eastern coast of Puerto Rico and Culebra
today and Friday, increasing to high during the weekend as a
northeasterly swell spreads across the local waters. Residents and
visitors are encouraged to stay informed by monitoring official
forecast updates as we approach the weekend.

&&

.SHORT TERM...Today through Saturday...

Clear to partly cloudy skies prevailed throughout the overnight
hours. A layer of low-level moisture persisted over the region,
resulting in scattered showers across the Atlantic waters.
Occasional light showers were also noted over land areas. Minimum
temperatures ranged from the low to mid-60s in higher elevations to
the mid to upper 70s in coastal areas. Very light winds were
observed due to a locally weakened pressure gradient, caused by a
surface-induced trough over the region.

For the remainder of the short-term forecast period, the area will
remain under the influence of a deep-layered trough. Upper-level
dynamics will generally remain favorable for convective activity;
however, moisture availability will be the key limiting factor in
the development of showers and thunderstorms. Precipitable water
(PWAT) values are forecast to peak near 1.4 inches this afternoon
and then decrease to below 1.0 inch tonight. These values are
considered near to below normal for this time of year. In addition,
mid-level relative humidity will remain well below normal, at or
below 10 percent. As a result, any convective activity is expected
to be primarily shallow and driven by diurnal heating and local
effects, mainly affecting interior portions of Puerto Rico during
the afternoon hours.

A more unstable and wetter pattern is expected to gradually develop
by Friday and persist through the weekend. PWAT values are forecast
to rise above climatological normals, reaching up to 1.9 inches by
Saturday night. In addition, mid-level relative humidity is expected
to increase significantly, reaching between 60 and 70 percent during
the same period. As a result, shower and thunderstorm activity is
likely to become more widespread across the local area. The threat
of urban and small stream flooding will remain elevated throughout
the weekend, although some uncertainty remains regarding the timing
of the most active period. Continue to monitor the weather forecast
as we approach the weekend.

.LONG TERM...Sunday through Thursday...

Model guidance continues to suggest a persistently wet and unstable
pattern from late this weekend into early next week. Deep tropical
moisture will stream into the region, with precipitable water
(PWAT) values well above climatological thresholds, ranging from
around 1.8 inches to about 2.2 inches from Sunday into mid- week,
then gradually decreasing by the end of the period, Thursday. A
mid to upper-level trough and an associated jet streak will
enhance lift and divergence aloft, creating favorable conditions
for showers and thunderstorm development. In addition, based on
the latest models, 500 mb temperatures will remain around
-8 degrees Celsius throughout the forecast period, maintaining
upper-level instability and supporting deeper convection.

At the surface, mainly easterly winds will dominate Sunday and
Monday, gradually shifting from the northeast Monday night into
Tuesday. According to the trend of the 925 mb temperatures, warmer
than normal conditions are expected during the weekend and early
next week, particularly in coastal and urban areas. A slight
cooling trend is expected from Tuesday onward.

The primary concern during this period is the increased risk of
flooding. Current model trends indicate that the highest potential
for moderate to heavy rainfall will occur between Sunday and
Tuesday, which could lead to localized flooding, particularly in
urban, low-lying, and mountainous areas. While there is still some
uncertainty regarding the exact timing of the heaviest rainfall,
the potential for impactful weather remains significant. Residents
and visitors are encouraged to stay informed by monitoring
official forecast updates as conditions may change quickly.

&&

.AVIATION...
(06Z TAFs)

Mainly VFR conditions expected to prevail. SHRA are expected to
develop after 17Z across the Cordillera Central, spreading toward
the west/northwest. Mtn top obsc likely through 24/23z. Winds are on
the light side and variable at 10 knots or less.

&&

.MARINE...

As the low weakens and dissipates to the north of our region, light
and variable winds will prevail through Friday, then moderate
easterly winds are expected to return by Friday night onward.
Overall conditions should remain favorable for small craft, though
localized hazardous marine conditions may develop near showers and
thunderstorms, which are expected to become more active during the
weekend into early next week.

&&

.BEACH FORECAST...

Today, there is a moderate risk of rip currents along the northern
and eastern beaches of Puerto Rico including Culebra, which means
life-threatening rip currents are still possible in those areas.
A low risk remains in place elsewhere. Similar conditions are
anticipated tomorrow, Friday. By Saturday, a northeasterly swell
will increase the risk to high, particularly along northern and
eastern exposed beaches of the islands.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
515 AM AST Fri Apr 25 2025

.SYNOPSIS...

Moisture content will start to increase today and tonight leading
to showers across the U.S. Virgin Islands and surrounding waters,
then scattered to numerous showers with isolated thunderstorms
this afternoon across the interior of Puerto Rico. A unstable and
wetter weather pattern will prevail during the weekend into next
week. A northeasterly swell will reach the Atlantic waters
resulting in a high risk of rip currents on Sunday. Residents and
visitors are encouraged to stay informed by monitoring official
forecast updates.

&&

.SHORT TERM...Today through Sunday...

Mostly clear skies and no shower activity prevailed throughout the
overnight hours, due to a persistent dry slot over the area. Minimum
temperatures ranged from the low to mid-60s in higher elevations to
the low to mid-70s in coastal areas. These values were slightly
cooler than the previous night, due to the absence of cloud cover.
Very light winds were observed, as the locally weakened pressure
gradient caused by surface-induced troughs has persisted in the
region.

The most recent satellite-derived precipitable water product shows a
moisture gradient over the region. Well below normal moisture values
are observed along a southwest-to-northeast oriented slot over
Puerto Rico, while abundant moisture is present in the vicinity of
Saint Croix. According to the 00Z Tropical Analysis and Forecast
Branch (TAFB) surface analysis, the forecast area is situated
between two surface troughs, with their axes located to the
northwest and southeast of the region. Favorable upper-level
dynamics also persist, as a mid- to upper-level trough remains in
place. This feature contributes to cool temperatures near 500 mb and
supportive jet dynamics, with southwesterly winds around 70 knots at
250 mb providing good ventilation aloft. This overall pattern can
support the development of showers and thunderstorms. However,
limited moisture continues to be a restricting factor.

Today, however, low- to mid-level moisture is expected to gradually
increase as the area of above-normal moisture near Saint Croix moves
closer to the region. Model guidance continues to show slight
variations in the timing of this moisture's arrival. Nevertheless,
this afternoon, the increasing moisture combined with surface
heating and local effects is expected to result in shower and
thunderstorm activity across the central interior and possibly the
north-central areas of Puerto Rico. This could lead to an elevated
flooding threat. During the evening and overnight hours, as the
broad area of above-normal moisture continues to gradually move
over the region, an increase in showers and isolated thunderstorms
is expected across the U.S. Virgin Islands, Vieques, Culebra, and
parts of eastern Puerto Rico. A limited flooding threat is
anticipated during this period.

For the remainder of the short-term forecast period, the areal
coverage of showers and thunderstorm activity is expected to
increase as favorable upper-level dynamics persist and combine with
well above normal moisture over the region. Model guidance indicates
that Sunday will likely be the most active day of the short-term
period. Continued urban and small stream flooding is anticipated
this weekend, along with the potential for landslides in areas of
steep terrain, particularly in locations that remain vulnerable due
to excessive rainfall during the past weekend.

.LONG TERM...Monday through Friday...

For the long-term period, model guidance continues to suggest a
persistently wet and unstable pattern early next week. A mid- to
upper-level trough and an associated jet streak will enhance lift
and divergence aloft, creating favorable conditions for the
development of showers and thunderstorms. Precipitable water
(PWAT) values are forecast to remain above climatological levels,
ranging from around 1.8 inches up to 2.2 inches at least through
midweek, then gradually decreasing by the latter part of the week.
Additionally, mid-level relative humidity is expected to increase
significantly, peaking at about two standard deviations above
average for this time of year.

Furthermore, based on the latest models, 500 mb temperatures will
remain around -8 to -9 degrees Celsius throughout the forecast
period, maintaining upper-level instability and supporting
continued thunderstorm development. The overall pattern suggests
showers will mainly affect our local waters and the U.S. Virgin
Islands during the overnight hours, reaching the northern and
eastern sectors of Puerto Rico in the mornings. As the days
progress, showers and potentially thunderstorms will become more
concentrated across the interior and western sectors of Puerto
Rico.

The primary concern during this period is the increased risk of
flooding, which is expected to remain elevated through at least
midweek. Current model trends indicate that the highest potential
for moderate to heavy rainfall will occur between Sunday and
Tuesday, which could lead to localized flooding, particularly in
urban, low-lying, and mountainous areas. While there is still some
uncertainty regarding the exact timing of the heaviest rainfall,
the potential for impactful weather remains significant. Residents
and visitors are encouraged to stay weather-aware and informed by
monitoring official forecast updates, as conditions may change
rapidly as uncertainty decreases in the coming days. We can expect
a gradual improvement in weather conditions toward the end of the
week, as a surface high-pressure system builds across the western
Atlantic and promotes a northeasterly wind flow that will push
drier air into the region.

&&

.AVIATION...
(06Z TAFs)

Mostly VFR conditions expected throughout the period. Vicinity
SHRA/TSRA possible at TISX through 15Z. Aft 17Z, SHRA/TSRA expected
to develop over interior Puerto Rico, potentially affecting the
vicinity of TJSJ and TJPS. Activity may result in brief reductions
in VIS and lowering of CIGs. Mountain obscuration likely across the
interior Cordillera Central. SHRA/TSRA may increase near TISX and
TIST aft 23Z. Winds light and variable early, becoming northeast at
up to 12 knots aft 14Z.

&&

.MARINE...

Light and variable winds will prevail through Saturday, then
moderate easterly winds are expected to return by Saturday night.
Overall conditions should remain favorable for small craft, but
localized hazardous marine conditions may develop near showers and
thunderstorms, which are expected to become more active tonight into
early next week. A long period northeasterly swell is expected to
spread across the Atlantic waters Saturday night into Sunday.

&&

.BEACH FORECAST...

Today, there is a moderate risk of rip currents along the
northwestern, northern and eastern coasts of Puerto Rico including
Culebra, which means life-threatening rip currents are still
possible in those areas. A low risk remains in place elsewhere.
The risk is expected to increase to high along north exposed
beaches by Saturday night into Sunday, as a northeasterly swell
will start to spread across the Atlantic waters.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
519 AM AST Sat Apr 26 2025

.SYNOPSIS...

A wet and unstable weather pattern is expected to continue through
at least the end of the workweek, bringing periods of heavy showers
and thunderstorms. Winds are forecast to remain light today,
promoting the development of slow-moving showers and thunderstorms.
Given the expected conditions, the potential for urban and small-
stream flooding remains elevated today. Additionally, a high rip
current risk is likely to return this evening and persist through at
least late Sunday night due to the arrival of a long-period
northerly swell.

&&

.SHORT TERM...Today through Monday...

During the past night and early morning hours, radar data showed
showers across parts of southeastern, eastern, and northeastern
Puerto Rico, as well as surrounding waters and nearby islands. The
heaviest rainfall initially fell in municipalities like Luquillo and
Fajardo, where about 2 to 3 inches were recorded, prompting urban
and small stream flood advisories. Later, showers tracked along the
coast, dropping up to 1 inch of rain, particularly in the Old San
Juan area. Since midnight, the highest radar estimated rainfall
totals have ranged from 0.30 to 1.00 inch. Overnight temperatures
ranged from the lower 60s in the mountains to the mid 70s across
urban and coastal areas of Puerto Rico and the U.S. Virgin Islands,
with light to moderate east northeast winds.

For the short-term period, model guidance continues to suggest a
persistently wet and unstable pattern. A mid to upper level trough
and an associated jet streak will enhance lift and divergence aloft,
creating favorable conditions for the development of showers and
thunderstorms, mainly today. According to the 00Z Tropical Analysis
and Forecast Branch (TAFB) surface analysis, the axis of the surface
trough is located just northwest of the region. Moisture content is
expected to increase from now onward, with model guidance suggesting
precipitable water (PWAT) values rising from around 1.5 inches
(average) to approximately 1.9 to 2.1 inches, which is above
climatological levels for this time of year, and will remain
elevated throughout the forecast period.

Additionally, mid-level relative humidity is expected to increase
significantly, peaking at about two standard deviations above
average. Furthermore, 500 mb temperatures will remain near minus 8
degrees Celsius, maintaining upper level instability and supporting
continued thunderstorm development. The overall pattern suggests
that showers will mainly affect local waters and the U.S. Virgin
Islands during the overnight hours, reaching the northern and
eastern sectors of Puerto Rico in the mornings. As the days
progress, showers and potentially thunderstorms will become more
concentrated across the interior and northwestern sectors of Puerto
Rico.

The primary concern today and likely over the next few days is the
increased risk of flooding, which is expected to remain elevated.
This means flooding in urban areas, roads, small streams, and washes
is likely, along with the potential for landslides in areas of steep
terrain. Isolated flash floods cannot be ruled out. Although the wet
pattern is expected to persist in the coming days, current model
trends indicate that the highest potential for moderate to heavy
rainfall will occur today, particularly during the afternoon hours.
Residents and visitors are encouraged to stay weather aware and
monitor official forecast updates.

.LONG TERM...Tuesday through Saturday...

For the rest of the week, a wet and unstable weather pattern will
persist. A series of shortwave troughs will move across the local
islands, maintaining favorable dynamical conditions aloft for the
development of showers and deep convective activity. As a result,
500 mb temperatures will remain between -8 and -9 degrees Celsius,
with relatively steep 850-700 mb and 700-500 mb lapse rates expected
through most of the long-term forecast period. Meanwhile, elevated
moisture levels will be present at all atmospheric levels, with
columnar moisture remaining well above normal for this time of year.

Most indicators, including precipitable water and the GFS Galvez-
Davidson Index (GDI), suggest that Wednesday will have the highest
chance of thunderstorms and heavier showers. This is when low-level
moisture convergence and steep lapse rates are expected to peak.
Wednesday also presents the greatest potential for widespread urban
and small stream flooding, as well as localized flash flooding,
particularly in areas that may have observed excessive rainfall in
previous days. However, similar risks will also exist on earlier
days, though with less areal coverage. It is important to note that
the timing of the most active day may shift as we approach the week,
depending on the simultaneous combination of favorable dynamics and
above-normal moisture levels. River streamflows will remain
elevated, especially across the interior of Puerto Rico. Therefore,
any additional rainfall could lead to rapid river rises in these
areas. Furthermore, saturated soils will enhance runoff, increasing
the risk of landslides in steep terrain.

Weather conditions will gradually improve by the weekend. However,
lingering moisture, combined with diurnal heating and local effects,
will continue to support afternoon convection across the interior of
Puerto Rico and downwind of the smaller islands.


&&

.AVIATION...
(06z) TAFS

Mainly VFR conds expected at all TAF sites this morning with
better chance of showers resulting in reduced vis across USVI this
morning. After 13Z-15Z VCSH will be likely across most TAF sites
and some may result in SHRA/VCTS reducing CIG/VIS and promoting
MVFR conds btwn 26/17Z-26/23Z. SHRA remains possible for TIST and
TISX after 26/23z. ESE light winds will prevail.

&&

.MARINE...

Light easterly winds will prevail through today increasing to
moderate tonight through early Sunday. Overall conditions should
remain favorable for small craft, but localized hazardous marine
conditions may develop near showers and thunderstorms through at
least midweek. A long-period northeasterly swell is expected to
spread across the Atlantic waters tonight into Sunday, which could
result in hazardous conditions for small craft, mostly across the
Atlantic waters.

&&

.BEACH FORECAST...

A moderate rip current risk will prevail across northern exposed
beaches for most of the day today. However, a long-period northerly
swell is expected to reach the northern coast and persist through
early Monday. Offshore buoy 41044 is already detecting this swell,
and according to these readings, the swell is expected to arrive by
this evening. As a result, a Rip Current Statement has been issued
for the northern beaches of Puerto Rico, from Aguadilla to Fajardo,
as well as the beaches of Culebra.

For more information, please refer to the latest Coastal Hazard
Message (CFWSJU) and Surf Zone Forecast (SRFSJU).

Residents and visitors in affected regions should heed warnings,
avoid swimming in these waters, and stay informed about updates from
local authorities.